Escape or ventilating hatches for buses, vans, and the like in recent years have been mounted in the hatch opening on an aluminum extrusion formed into a square or rectangular shaped ring and secured within the hatch opening of the vehicle. Such rings have been of such large manufacturing tolerances that it has often been difficult to effect a weathertight seal between the ring and hatch. In addition, manufacturing tolerances for such rings and the somewhat flimsy construction thereof has made it necessary to provide special mounting plates for the escape hatches. One such escape hatch is shown in U.S. Pat. No. 4,021,073, with the mounting plates being designated at 22 and 122. Such patent is incorporated in this disclosure by reference. Because of such plates, it is difficult to cover or conceal the rings with a trim molding, and therefore the hatch mounting has an "unfinished" appearance.
While it would be possible to manufacture an aluminum mounting ring of sufficiently close tolerances that an effective weathertight seal between the ring and the escape hatch could be made, the cost thereof would render the hatch very expensive. Accordingly, I have sought to provide a mounting ring which will be of strong and durable construction and of sufficiently close manufacturing tolerances that an effective weathertight seal between it and the hatch may be provided. In addition, I have sought to provide a mounting ring which avoids the use of the aforesaid mounting plates and thus enables ready association with the ring of a trim molding to give a finished appearance to the hatch frame.